Some people need to chill out. But $900... (Pounds, euros, dollars, not sure so I took a shot in the dark with currency.)

Dollars it is.

O.o probably already tried but ill put it out there anyway. Have you tried newegg.com?

:O awesome site is awesome. Thx

any time ^^ <3

have to talked to the geniuses at your local apple store?

gah i love macs but damn they are allot to buy and repair ...still wont see me on a PC though ha

underpowered, overpriced and a pain to fix. Mac summed up. Are you sure it's the mobo though? and if you have a laptop, a sata/ide to usb convertor should cost no more than 24$

Oh man, sorry to hear. Can imagine that it would cost a lot, it's an iMac right? Got a MacBook myself and having lots of problems with it, but don really feel like paying 500 dollar to have it checked out and fixed. Just to have the same problem again.

Hope you get it fixed!

Do Apple Motherboards seriously cost $900?

Yup. If its an old model sometimes they are just under $400. I've got a couple old MacBooks I was given (not Pros unfortunately). One wouldn't power and the other had bad video, so I figured it was the logic boards and sourced them. They were $350 and $400. Totally wasn't worth it to fix them since they were already 4-5 years old, but it turns out that nicer one that wouldn't power just had a bad mag-safe board, which only a $40 part, but I stole it from the other one. Freaking Apple.

This is why I do not like Mac. And before anyone starts flaming me as a "PC fanboy", I my first computers were Macs, at school we mostly used Mac, I was an Apple Certified Repair Technician for 6 years at my first job, and currently I develop software that also targets Macs, so lol.
If you discount the space saving, the All-In-On design has nothing by drawbacks in terms of servicing. Apple specific replacement parts are ridiculously expensive even if its a common model since even for-parts units of current models sell for a lot because so many others are trying to repair the same problems too. I bought a mid-2012 MiniMac for a build server with the understanding that if anything does break on it, I'm gonna have to buy some special tools just to the silly thing (and if I ever do that, I'll get the expensive cable kit too and add the 2nd HDD :p).

I'm guessing you tried all the common logic board fixes already, zapping, battery, etc. You can try looking on eBay for the same model that has just a broken screen, but that's usually rare and iffy.

All I did was replace the hard drive in the hopes that the Install disc would boot up. But I still get the same grey screen with no response from a key board. I didn't know enough about motherboards to try anything else.

Any suggestions?

Have you tired holding the cmd opt P and R keys during boot yet?

All praise the god of obsolescence...

LOLOLOL Macs suck ass.

lol. Ass.

One of the reasons I use a PC. Apart from the stability of a proper custom rig, the competition on the parts market means you don't have to offer your kidney as a collateral to get it fixed. Still, losing a computer sucks. I burned out my power supply last year, the first such failure of its kind in six years, right before moving (four days before the move).

I have an iMac like that and have taken it apart to upgrade the hard drive. Looks like you did a pretty good job.

Macs grey-screen? o uo;;